UC San Diego

Purpose To evaluate the accuracy of detection based on level of interpreter experience when reporting coronary artery calcium (CAC) on dual-energy (DE) posteroanterior (PA) and lateral chest radiographs and demonstrate the accuracy of specific imaging clues. Materials and Methods Retrospective review of 45-70-year-old patients who underwent DE PA and lateral chest radiography between March 1, 2021, and June 30, 2021, and also underwent noncontrast chest CT scan within 3 years. Following instruction of DE principles and the appearance of CAC, seven readers interpreted the DE chest radiographs to state if CAC was possibly present, definitely present, or not present; estimate ordinal CAC score; and report imaging clues present. Results Ninety-nine patients were selected (mean age, 58.6 years; 53 male and 46 female patients). Among the 62 patients with CAC, the median score was 92. The median CAC score among seven readers when detected ranged from 120 to 203 and when not detected ranged from 18.9 to 39. Among all readers, sensitivity ranged from 71% to 84% in detecting CAC as possibly or definitely present with a specificity range of 54%-92%, and the area under the receiver operating characteristic curve range was 0.767 to 0.906. The interreader agreement κ statistic ranged from 0.488 to 0.750. Conclusion DE lateral chest radiographs demonstrated CAC better than DE PA radiographs, with relatively high accuracy and with moderate and substantial interreader agreement. Preclinical detection of CAC presents an opportunity for early intervention in coronary atherosclerotic disease, which may be augmented by machine learning tools. Keywords: Dual Energy Chest Radiography, Lateral Chest Radiography, Lateral Chest X-ray Coronary Calcium, Coronary Calcium Screening, Coronary Calcium Detection Supplemental material is available for this article. © RSNA, 2025.